MOLISENS: MObile LIdar SENsor System to exploit the potential of small industrial lidar devices for geoscientific applications Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-11-247-2022 31 October 2022 We propose a newly developed modular MObile LIdar SENsor System (MOLISENS) to enable new applications for small industrial light detection and ranging (lidar) sensors. MOLISENS supports both monitoring of dynamic processes and mobile mapping applications. The mobile mapping application of MOLISENS has been tested under various conditions, and results are shown from two surveys in the Lurgrotte cave system in Austria and a glacier cave in Longyearbreen on Svalbard. Read more
Trends in the tropospheric general circulation from 1979 to 2022 Weather and Climate Dynamics DOI 10.5194/wcd-3-777-2022 28 October 2022 This study of changes in temperature and wind since 1979 met its twin aims of (i) increasing confidence in some findings of the latest IPCC assessment and (ii) identifying changes that had received little or no previous attention. It reports a small overall intensification and shift in position of the North Atlantic jet stream and associated storms, and a strengthening of tropical upper-level easterlies. Increases in low-level winds over tropical and southern hemispheric oceans are confirmed. Read more
Soil carbon loss in warmed subarctic grasslands is rapid and restricted to topsoil Biogeosciences DOI 10.5194/bg-19-3381-2022 26 October 2022 In subarctic grassland on a geothermal warming gradient, we found large reductions in topsoil carbon stocks, with carbon stocks linearly declining with warming intensity. Most importantly, however, we observed that soil carbon stocks stabilised within 5 years of warming and remained unaffected by warming thereafter, even after > 50 years of warming. Moreover, in contrast to the large topsoil carbon losses, subsoil carbon stocks remained unaffected after > 50 years of soil warming. Read more
Root-mean-square error (RMSE) or mean absolute error (MAE): when to use them or not Geoscientific Model Development DOI 10.5194/gmd-15-5481-2022 24 October 2022 The task of evaluating competing models is fundamental to science. Models are evaluated based on an objective function, the choice of which ultimately influences what scientists learn from their observations. The mean absolute error (MAE) and root-mean-squared error (RMSE) are two such functions. Both are widely used, yet there remains enduring confusion over their use. This article reviews the theoretical justification behind their usage, as well as alternatives for when they are not suitable. Read more
The eWaterCycle platform for open and FAIR hydrological collaboration Geoscientific Model Development DOI 10.5194/gmd-15-5371-2022 21 October 2022 With the eWaterCycle platform, we are providing the hydrological community with a platform to conduct their research that is fully compatible with the principles of both open science and FAIR science. The eWatercyle platform gives easy access to well-known hydrological models, big datasets and example experiments. Using eWaterCycle hydrologists can easily compare the results from different models, couple models and do more complex hydrological computational research. Read more
Towards a self-sufficient mobile broadband seismological recording system for year-round operation in Antarctica Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-11-235-2022 19 October 2022 We present a mobile and self-sufficient seismometer station concept for operation in polar regions. The energy supply can be adapted as required using the modular cascading of battery boxes, wind generators, solar cells, or backup batteries, which enables optimum use of limited resources. Our system concept is not limited to the applications using seismological stations. It is a suitable system for managing the power supply of all types of self-sufficient measuring systems in polar regions. Read more
A probabilistic framework for quantifying the role of anthropogenic climate change in marine-terminating glacier retreats The Cryosphere DOI 10.5194/tc-16-2725-2022 17 October 2022 Marine-terminating glaciers have recently retreated dramatically, but the role of anthropogenic forcing remains uncertain. We use idealized model simulations to develop a framework for assessing the probability of rapid retreat in the context of natural climate variability. Our analyses show that century-scale anthropogenic trends can substantially increase the probability of retreats. This provides a roadmap for future work to formally assess the role of human activity in recent glacier change. Read more
Stable water isotope signals in tropical ice clouds in the West African monsoon simulated with a regional convection-permitting model Atmospheric Chemistry and Physics DOI 10.5194/acp-22-8863-2022 14 October 2022 The Earth’s water cycle contains the common H2O molecule but also the less abundant, heavier HDO. We use their different physical properties to study tropical ice clouds in model simulations of the West African monsoon. Isotope signals reveal different processes through which ice clouds form and decay in deep-convective and widespread cirrus. Previously observed variations in upper-tropospheric vapour isotopes are explained by microphysical processes in convective updraughts and downdraughts. Read more
Technical note: Conservative storage of water vapour – practical in situ sampling of stable isotopes in tree stems Hydrology and Earth System Sciences DOI 10.5194/hess-26-3573-2022 12 October 2022 We developed a method of sampling and storing water vapour for isotope analysis, allowing us to infer plant water uptake depth. Measurements can be made at high temporal and spatial resolution even in remote areas. We ensured that all necessary components are easily available, making this method cost efficient and simple to implement. We found our method to perform well in the lab and in the field, enabling it to become a tool for everyone aiming to resolve questions regarding the water cycle. Read more
The Great Lakes Runoff Intercomparison Project Phase 4: the Great Lakes (GRIP-GL) Hydrology and Earth System Sciences DOI 10.5194/hess-26-3537-2022 10 October 2022 Model intercomparison studies are carried out to test various models and compare the quality of their outputs over the same domain. In this study, 13 diverse model setups using the same input data are evaluated over the Great Lakes region. Various model outputs – such as streamflow, evaporation, soil moisture, and amount of snow on the ground – are compared using standardized methods and metrics. The basin-wise model outputs and observations are made available through an interactive website. Read more
Stratigraphic templates for ice core records of the past 1.5 Myr Climate of the Past DOI 10.5194/cp-18-1563-2022 7 October 2022 Projects are underway to drill ice cores in Antarctica reaching 1.5 Myr back in time. Dating such cores will be challenging. One method is to match records from the new core against datasets from existing marine sediment cores. Here we explore the options for doing this and assess how well the ice and marine records match over the existing 800 000-year time period. We are able to recommend a strategy for using marine data to place an age scale on the new ice cores. Read more
A physical concept in the press: the case of the jet stream Geoscience Communication DOI 10.5194/gc-5-177-2022 5 October 2022 In this paper, we discuss the instrumental role of the press in informing and educating the public on the subject of climate science and climate change. We illustrate this using an example of a dissemination format called Weather Stories, published daily in one of the most read newspapers in Spain. The particularities of this journalistic format are described using a practical example of a relatively complex physical concept: the jet stream. Read more
Clouds drive differences in future surface melt over the Antarctic ice shelves The Cryosphere DOI 10.5194/tc-16-2655-2022 3 October 2022 Model projections suggest large differences in future Antarctic surface melting even for similar greenhouse gas scenarios and warming rates. We show that clouds containing a larger amount of liquid water lead to stronger melt. As surface melt can trigger the collapse of the ice shelves (the safety band of the Antarctic Ice Sheet), clouds could be a major source of uncertainties in projections of sea level rise. Read more
A tectonic-rules-based mantle reference frame since 1 billion years ago – implications for supercontinent cycles and plate–mantle system evolution Solid Earth DOI 10.5194/se-13-1127-2022 30 September 2022 We have built a community model for the evolution of the Earth’s plate–mantle system. Created with open-source software and an open-access plate model, it covers the last billion years, including the formation, breakup, and dispersal of two supercontinents, as well as the creation and destruction of numerous ocean basins. The model allows us to “see” into the Earth in 4D and helps us unravel the connections between surface tectonics and the “beating heart” of the Earth, its convecting mantle. Read more
Black carbon aerosol reductions during COVID-19 confinement quantified by aircraft measurements over Europe Atmospheric Chemistry and Physics DOI 10.5194/acp-22-8683-2022 28 September 2022 The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %. Read more
Impact of freshwater runoff from the southwest Greenland Ice Sheet on fjord productivity since the late 19th century The Cryosphere DOI 10.5194/tc-16-2471-2022 26 September 2022 One of the questions facing the cryosphere community today is how increasing runoff from the Greenland Ice Sheet impacts marine ecosystems. To address this, long-term data are essential. Here, we present multi-site records of fjord productivity for SW Greenland back to the 19th century. We show a link between historical freshwater runoff and productivity, which is strongest in the inner fjord – influenced by marine-terminating glaciers – where productivity has increased since the late 1990s. Read more
Towards automatic finite-element methods for geodynamics via Firedrake Geoscientific Model Development DOI 10.5194/gmd-15-5127-2022 23 September 2022 Firedrake is a state-of-the-art system that automatically generates highly optimised code for simulating finite-element (FE) problems in geophysical fluid dynamics. It creates a separation of concerns between employing the FE method and implementing it. Here, we demonstrate the applicability and benefits of Firedrake for simulating geodynamical flows, with a focus on the slow creeping motion of Earth’s mantle over geological timescales, which is ultimately the engine driving our dynamic Earth. Read more
The 852/3 CE Mount Churchill eruption: examining the potential climatic and societal impacts and the timing of the Medieval Climate Anomaly in the North Atlantic region Climate of the Past DOI 10.5194/cp-18-1475-2022 21 September 2022 We assess the climatic and societal impact of the 852/3 CE Alaska Mount Churchill eruption using environmental reconstructions, historical records and climate simulations. The eruption is associated with significant Northern Hemisphere summer cooling, despite having only a moderate sulfate-based climate forcing potential; however, evidence of a widespread societal response is lacking. We discuss the difficulties of confirming volcanic impacts of a single eruption even when it is precisely dated. Read more
Lessons from the 2018–2019 European droughts: a collective need for unifying drought risk management Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2201-2022 19 September 2022 Recent drought events caused enormous damage in Europe. We therefore questioned the existence and effect of current drought management strategies on the actual impacts and how drought is perceived by relevant stakeholders. Over 700 participants from 28 European countries provided insights into drought hazard and impact perception and current management strategies. The study concludes with an urgent need to collectively combat drought risk via a European macro-level drought governance approach. Read more
Effects of climate change in European croplands and grasslands: productivity, greenhouse gas balance and soil carbon storage Biogeosciences DOI 10.5194/bg-19-3021-2022 16 September 2022 Crop and grassland production indicates a strong reduction due to the shortening of the length of the growing cycle associated with rising temperatures. Greenhouse gas emissions will increase exponentially over the century, often exceeding the CO2 accumulation of agro-ecosystems. Water demand will double in the next few decades, whereas the benefits in terms of yield will not fill the gap of C losses due to climate perturbation. Climate change will have a regionally distributed effect in the EU. Read more